This section provides background information related to the present disclosure which is not necessarily prior art.
In a network management system based on Simple Network Management Protocol (SNMP), it is necessary to get message for state changes and configuration changes of device nodes in the network in time. Many network management systems apply a method for periodically reading device data, i.e., for polling device data. When there are a huge number of devices, the polling operation will expense a lot of network resources, so a dispatching method for the polling is necessary.
At present, the dispatching methods usually take a device as a unit or a type of devices as a unit for dispatching. When a device is taken as a unit, a polling period is set for each device, data of the device are read once every period and introduced into the network management system. When a type of devices are taken as a unit, a polling period is set for each type of devices and every period devices of the type are polled sequentially for reading data of each device.
When there are small number of devices, such as several devices or tens of devices, the prior dispatching method works well and can be simply implemented. Nevertheless, many devices, such as hundreds and thousands of devices, can cause complications.
When a device is taken as a unit for dispatching, first, control for every device will occupy a lot of system resources, so the system is over loaded and normal operation of other network management functions will be affected. Secondly, it is impossible to make coordination between devices, so it is possible that a lot of devices are polled in the same duration, which will cause a burst network flow and system load on the network and in a serious situation the network will be blocked. In this way, the network management system will collapse due to overload, normal running of network service will be affected in the case that inner-band network management is used. Thirdly, if there are a lot of devices, independent configuration for polling period of each device will greatly increase work load of network administrator, and increase the difficulty of management and operation.
When a type of devices are taken as a unit for dispatching, the burst flow caused by polling management information is controlled in a certain degree and the configuration of polling period is simple, but since all devices are sequentially polled, the polling period is long and the real time response ability is worse, system resources and network bandwidths cannot be utilized sufficiently. When users demand the change of network management system should have a high real-time ability, this dispatching method cannot satisfy the requirement. In addition, there is little coordination between various types of devices, and all devices are processed jointly, so individuation cannot be realized.
Besides, changeability of data on a device is different but the prior dispatching method reads all data on a device with the same period, so various data on the same device cannot be control individually. Therefore, it is impossible to have a shorter period for the data that change frequently and a longer period for the data that change rarely.
In addition, the prior dispatching methods can only control the polling period but cannot control the polling time, so it is impossible to distribute the polling to the idle time of services on the network in the case of inner-band network management.